1. Technical Field
The present disclosure relates to an aperture controlling system.
2. Description of Related Art
Most current digital cameras use Charge Coupled Devices (CCDs) to convert optical signals into electronic signals. However, the CCD must be supplied with 12 volts direct current to drive charges of each pixel of the CCD to move into an associated transmission channel. As a result, the CCDs must include numerous complicated circuits. As an alternative, Complementary Metal Oxide Semiconductor (CMOS) sensors, which are low-cost, low power consuming, and high integratable, become more and more favored by consumers.
In general, an aperture of a digital camera is controlled by an aperture driving circuit that must use NTSC/PAL signals output from the CCD. However, if a CMOS is equipped in a camera instead of a CCD, the aperture driving circuit would not be able to function properly because the image signals output from the CMOS are digital video signals unsuitable for use in the original aperture driving circuit to control the aperture.
Therefore, it is desirable to provide an aperture controlling system which can overcome the above problems.